This invention concerns attachment methods for mounting a speaker grille to a panel structure in which a speaker opening is formed.
Speakers for audio equipment are normally enclosed for protection, and an opening in the enclosure structure allows for emanation of the sound. This speaker opening is covered with a speaker cover grille or cloth covering.
In automotive applications, the speaker is recessed within an opening in a trim panel, and the cover for the opening must be of a durable, attractive material compatible with the interior trim. The method of attaching the cover must not involve the use of exposed fasteners, as this is considered aesthetically unacceptable in modern auto interior design.
These requirements have led to the use of molded plastic speaker cover grilles using integrally formed assembly features. Perforated metal speaker covers have been used as they provide an attractive appearance, but assembly in auto applications has involved greater cost than for molded plastic covers, as a separate plastic border is required. The plastic border also decreases the open area available for the passage of the sound from the speaker. While spring steel retainer tabs could be used, the addition of these would also increase the cost to be in excess of molded plastic covers.
The metal of the cover itself must be constructed of a mild, cold-rolled steel, in order to be able to be perforated, but this material does not have sufficient resilience to itself act as a conventional spring tab.